Tool or apparatus for applying coating



Oct. 4, 1927. f 1,644,081

' J. J. PREBLE TOOL OR APPARATUS FOR APPLYING COATING Filed May 8,. 1924 2 Sheets-Sheet l J. J. PREELE Oct. 4 1927.

TOOL OR APPARATUS FOR APPLYING COATING Filed May 8, 19,24 2 Sheets-Sheet Patented Oct. 4, 1927.

UNITED STATES JAMESJARVIS PREBLE, F NEWTON, MASSACHUSETTS.

TOOL OR APPARATUS FOR APPLY'ING COATING.

Application led Hay 8, 1824. Serial No. 711,829.

This invention relates to tools or apparatus for applying coating to surfaces,- the presentapplication being a continuation as to certain common subject matter of my co.- pcnding application Serial No. 540,568, filed March 2, 1922.

The coating, if a liquid may be a paint, japan, varnish or other suitable coating medium or, if desired, it may be a solid in powdered form. The material or surface to which the coating is to be applied maybe of any character such, for example, as wood, metal, or other material.

In theaccompanying drawings:

Fig. 1 is a. vertical, longitudinal section taken substantially centrally through the tool or apparatus;

Fig. 2 is a horizontal, longitudinal Section through the body of the tool or apparatus shown in Fig. 1;

Fig. 3 is a front elevation of the upper portion of the tool or apparatus;

Fig. 4 is a side elevation upon a smaller scale of the tool or apparatus;

Fig. 5 is a horizontal section on the line 5-4-5 of Fig. 4 looking in the, direction of the arrows.

Referring more particularly tothe drawings the tool, apparatus,` or appliance of my invention is adapted for use in any relation for applying coating but in practice has found particularly wide u:e as a so-called .spray gun for applying paint to metallic, wooden or other surfaces. In the disclosed embodiment of my invention the tool, appliance, or apparatus comprises generally a body portion indicated as a whole at l and including a forward section 2 and a rear section 3. The tool also comprises a paint or coating container 4, a cover 5 for the latter preferably form-ed integrally with the body portion of the tool and herein the front section 2 thereof, and a handle portion 6 suitably secured to the tool body and herein to the rear section 3 of the latter.

The container 4 is of any suitable material, as metal or glass and is adapted to be filled to the desired extent with paint or other coating -material to be supplied or drawn therefrom as hereinafter described through a pipe 7 extending through' the Acontainer cover and threaded as at 8 into a suitable socket or opening in the front section 2 of the tool. Upon the upper extremity of said container 4 is directly received the body of the tool, said cover 5 being shown as having a circular or other suitably shaped depending flange 10 to fit over the upper end of the container. Herein I have shown a suitable gasket 12 positioned intermediate the cover and the container.

Said container and tool body are adapted to be secured together in any suitable manner afl'ordin ready removal of the container when desire In the resentform of my invention I have provi ed a turned over or otherwise reinforced portion 13 at the upper end of the container vvhereon arepro vided a plurality of preferably equally spaced, laterally projecting lugs 14, three being shown herein, see Fig. 5. Said lugs are shown as rivets or may be formed integrally with the container, if desired, and are adaptl ed to cooperate with a suitable receivingfrmation upon the cover ortion 5 of the tool. Herein there is provide upon the inner surface of said dependingflange 10 va series of partial threads, wedge formations, or the like, 15 (see Fig. 1), forming slightly inclined tracks or grooves 16 in which the lugs may be received. Each such groove terminates at its lower end in a downwardly open notch or recess 17, spaced similarly as the lugs 14 and of a dimension to receive the same. y

To secure the container to the spraying tool 1 it is necessary merely to insert the container within the flange 10 of the cover portion, with the lugs 14 positioned in the respective notches 17 and then relatively to rotate slightly the container and tool 1n a direction to cause the lugs to ride up along the tracks or grooves 16, whereby the container is wedged up against and firmly held in secured position upon the tool. Removal of the container may subsequently be readily effected by a similar but reverse operation. The gasket 12 is prevented from dropping out of the cover when the container 1s detached therefrom by the tracks or grooves 16 (Fig. 1). This is a great practical convenience. 4

The tool or appliance of lmy invention lis particularly intended for use where a relatively small quantity of the coating material is carried by and with tlie` tool rather than supplied thereto from astructurally separate container in communication with the tool through flexible piping or the like. An important objectof my invention is to provide an .inexpensively manufactured yet thoroughly eicient tool for the purpose and particularly where but a comparatively small quantity of coating material is -re quired for the job or work, or where changes in material are frequent. The body of the tool is desirably ofl metal and as shown in each of the figures it is formed integrally with the cover for the container. As best seen in Figs. 1, 2, and 3 the cover is formed transversely thereof and herein substantially diametrically with a wall 24 enclosing a chamber 25 communicatl ing at its forward end with a longitudinally extending passage 26 leading to the front extremity of the forward section 2 of the tool body. Said passage 26 is in turn in communication with a jet orifice 27 formed in av nose piece 28 threaded, or otherwise, but preferably removably secured at fthe extremity of said forward section 2, said nose piece having an inclined and generally coneshaped outer surface. Said forward section of the tool body is threaded as indicated at 29 to receive the internally threaded cap 30 ,having a central orifice 31 and an inclmed inner `surface 32, a lock nut 33, if desired, being threaded on to the body in the rear of said cap 30. Said inclined inner surface 32?- of the cap cooperates with the similarly enclose'd outer surface of the nose piece to provide a circular or circumferential sleeve-like, space of adjustable cross dimension and into which the coating material is drawn to form I a layer or film surrounding the central streamw of motive agent issuing at the jet orifice 27.

The motive agent which preferably is air underl pressure, is conveyed as hereinafter described into the chamber 25 where it is discharged against the layer or film-like supply or accumulation of coatingl material between the nose piece 28 and the cap 30. The thickness of said layer or film of coating material may be regulated by adjusting the cap 30 longitudinally upon the forward portion of the tool body or, if desired, the supply of coating' material maybe shut off entirely by bringing said cap into contact with the nipple 28. Said cap is readily removable for cleaning or other purposes and if desired a plurality of interchangeable caps having orifices of different diameters may e provided. Said'nose-pieceis also readily removable, as shown, and a number of such pieces having jet orifices of different sizes may be interchangeably employed, if desired.

It will be observed that the motive agent is centrally applied and the paint or coating material is supplied as anI annular layer or film surrounding the air passage. The paint or like material is drawn on to or deposited upon and received by the outer and inclined surface of the nose-piece 28, that, is, between said surface and the'inclined inner surface '32 of the cap 30. The said paint or material is supplied or drawn into the annular space described through the suction or c0111- agent or-air under pressure supplied,V tothe passage 26. 'Ihe rush ofthe motive agent or an" induces a suction or vacuum Within the interior of the cap 30 which is in communf cation with the supply ofV coating ,materialinf the container by means of one or more longitudinal passages 34, see Fig. 1,"in com-- munication with the supply pipe7 drawing therethrough a supply of coatingY material to be deposited between the nose-piecc 28 and c ap 30 for discharge together with the motive agent as a mist or cloud. lVith the construction described the coating material 'in the container is not under pressure but is drawn or supplied from the container in the manner disclosed. The air in the container above the level of the coating material is preferably maintained at atmospheric pressure as by means of the small opening 35 in the cover; see Fig. 2.

Desirably I provide means for supplementally discharging the air or other motive agent onto the discharge cloud or mass of paint or coating material and the main discharged air` to produce, when desired, a wider or fan-shaped spray of variable width and thickness. For this purpose I have herein represented the body portion. of the tool as having a passage l36, see Fig. 1, in communication with the longitudinal passage'26 and extending substantially radially outwardly through the wall of the tool body. Mounted upon the forward portion of said tool'body and to the rear of the nut 33 is a cylindrical head or sleeve 37 carrying at diametrically opposite points thereon the supplemental jet members 38, 38 extending substantially in parallelism with the main air passage.I The passage 36 is in communication with a transverse passage 39 formed in the head 37, said transverse passage as shown extending completely about the tool body and being in communication, at opposite sides of the latter, with the longitudinal passages 40, 41 in the supplemental jet members respectively. Near their forward 'bined suction and ejector effect ofthe motive ifi" ends said passages 40. 41 are provided with inclined discharge orifices 42, 43 whereby the air is supplementally dischargedl upon the mass or cloud of paint and the primarily n discharged air to effect the spreading or flattening of the same. y

The supplemental air discharge is desirably readily controllable and for this purpose I have provided a valve 44 having anv inclined lower end 45 adapted to seat against the similarly formedupper end of the passage 36 so as to cut off entirely or to controlA the` flow'` of air therethrough. Referring particularly to Fig. 1, said valve 44 is secured at its upper end to a valve operating member shown as a cap 46 desirably having a knurled or rough exterior surface 47, and

interiorly threaded as indicated at 48 to engage a thread upon the outer surface of a boss or extension 50 on the supplemental jet.

head or sleeve 37. Said boss 50 is itself interiorly threaded to receive the threaded bushing 51 securing in place a suitable packing 52. The construction is such that the valve is thoroughly packed against the escape of the supplemental air but may be readily manipulated, and is at the same time of rugged construction and so protected as not to be easily broken in the use of the tool.`

Referring to Figs. 1 and 2, the adjacent ends of the forward and rear body sections 2 and 3 are interiorly threaded to receive the interconnecting threaded nipple 53, said sections bcing preferably locked in proper alignment as by means of the screw 54 extended upwardly through the cover 5 and tapped into said rear body portion 3. Said nipple accords communication for the air between the chamber 25 on the forward body section 2 and the elongated chamber 55 in said rear body portion.

Certain varnishes, enamels and like coating materials fiow out better, resulting in a better finishing, if the air or motive agent is heated. Accordingly when desired I may provide means for heating the air or other motive agent prior to its discharge from the tool, such means being optional and not an essential feature of my present invention. Any suitable means may be employed for this purpose but preferably I provide an electr1cal resistance unit indicated diagrammatically at 56 the same bein received in said elongated chamber 55. aid chamber is preferably formed with an internal spiral rib 57 which surrounds with a tight fit said resistance unit so as to compel the air or other motive agent which enters the rear of said chamberthrough the passage 58 to circulate about the resistance unit during its forward travel and thus to be effectively heated. The section 3 of the body at its rear or right hand end, viewing Fig. 1, desirably is slightly enlarged and lslcored internally as indicated at 59 to receive an externally threaded collar 60 which secures in place a plug 61 `of suitable insulating materlal and through which extend suitable termmalsl 62, 63 electrically connected at their inner ends with said resistance unit 56.. ySaid terminals are adapted to be connected with any suitable source of electricity in a manner, not necessary herein more fully to describe. At such times ywhen the heating means is not to be employed the same may be removed from the tool substantially as a unit and an imperforate plug of the same outside dimension` as the collar 60 em thetool body, or t e heater may be left in the tool and the extension chord merelydisshown is formed with an integral depending loyed to close the rear ofl portion 64 in which is formed a horizontally extending` recess 65 in communication with the passage 58 constituting the inlet for the air to the chamber 55 and also in communication with a downwardly extendin passage 66. At its forward or left hand en Fig.' 1, said recess 65 is of enlarged diameter and interiorly threaded as at 67 to receive a valve plug 68- the latter having threaded into its outer and recessed end a valve gland 69 securing in place suitable packing 70. Extending axially throu vh said valved plug and packing is the stem 1 of a valve 72 adapted to take against the valve seat 73 of said valve plug 68. A coil spring 74 1s employed to hold the valve 72 normally against its seat but yieldable to pressure brought u on a suitab e manipulatin member such, or example, as the trigger pivoted at 76 upon the tool body. The handle of the gun is preferably slightly rearwardly inclined as shown and is comprised in. part by said depending portion 64 formed integrally with the tool body section 3 and in part by the handle member 6 previously mentioned. Said handle portion 6 is formed exteriorly as a continuation of said depending portion -64 and is suitably shaped to fit the land of the operative. Desirably said handle portion 6 is hollow so as to provide a relatively large chamber 77 having communication at its upper end with the downwardly extending passage 66 of said depending portion 64. The tool body proper and said handle portion 6 are secured together in any suitable manner. preferably by the threaded nipple 78 received in aligned recesses in the adjacent portions of said handle and portion 64, a lock screw 79 engaging both said members being provided, if desired. Extending through sald air passage 66 and nipple and downwardly lnto said chamber 77 in the handle but terminating a substantial distance above the bottom wall thereof is a tube 80.

Said chamber 77 in the handle of the tool is adapted to receive, desirably at or near' its lower extremity, a hose 81 which is in communication with a suitable source of motive 'agent as air under pressure. Said hose 81 is coupled or otherwise secured to a nipple 82 threaded into the handle portion and from which exten-ds upwardly an open ended tube 83. Said tube 83 is desirably of suiiicient len h .to project beyond the lower open end of t e tube and is out of alignment with the latter. Said chamber 77 and associated parts constitute a trap or separator for water or moisture and oil or other liquid or foreign matter, affording means, herein self-contained within the tool or appliance, for removing and collecting the water and oil or other liquid which may be 'carried by the motive agent such as air under pressure. Particles of water,such as may at tunes collso A lect lin the conductors for the motive agent as by condensation or in any other manner, upon entering the chamber 7 7 in the handle ot' the tool cannot pass directly to the tube 80 but will be trapped and retained within said chamber thereby preventing them from mixing with and injuring the coating material. At the lower portion of sai-d chamber lfhave provided an outlet 84 normally closed by a pet-cock or like member 85 whichV may be opened to ellect the discharge of the collected water when desired. It said pet-cock is opened while the motive agent 1s being supplied, such water will be blown out through said outlet 84.

My invention lis not confined to the particular structure of water and oil separator shown as any suitable means may be employed for the purpose; in some instances where the separator is not necessary, as where an external separator is employed, I may omit the same, storming the handle either as shown or otherwise, as for example, in the manner similar to that shown in my said copending application.

It will be observed that the entire tool is exceedingly compact being composed of three main parts, namely the container, the handle, and the body portion, the latter as shown being Jformed in two sections. But a single valve is required, namely, that controlling the supply of the motive agent since the coating material is drawn in the manner above described from the supply within the container, said supply being under atmospheric pressure only. No separate valve is necessary to control the volume of coating f discharged as by varying the degree of vacuum elfectively exerted through the coating conduit, since this is regulatable by adjustment of the threaded cap 30 toward or away from the nose-piece 28, both of said pieces being replaceable/if desired, as for instance when handling coating matreials of greater or less density or more or less viscosity, by similar pieces having larger or smaller orices.

It will also be understood that in accordance with my invention the supplement-al jet head and passage 36 may be omitted if no spreading means is desired. Said supplemental jet or spreader means, however, particularly cooperates with the apparatus shown since by closing the valve 44 the tool may be employed Without spreading effect, or such effect may be obtained to any desired extent by adjustment of said valve. Also it is not essential that the disclosed means for heating the mot-ive agent be employed since other suitable means may be used for the purpose or the motive agent may be employed without heating.

My invention is not limited to the partieular illustrative embodiment thereof herein disclosed.

l. A spray gun having, in combination, a body portion, a cover carried thereby provided with a circumferentially depending flange having a plurality of independent inclined tracks thereon, a plurality of vertical notches in the flange communicating respectively with the tracks, a container provided with a plurality of projecting lateral lugs constructed and arranged to enter the notches between the tracks by a relative-vertical movement of the cover and the container and to enter the tracks from said notches by a relative rotative movement of the cover and the container.

, 2. A spray gun having, in combination, a body portion, a cover carried thereby provided with a circumferentially depending flange having a plurality of independent inclined tracks thereon, a plurality of vertical notches in the flange communicatmg respectively with the tracks, a container provided with a plurality of projecting lateral lugs constructed and arranged to enter the notches between the tracks by a relative vertical movement of the cover and the container and to enter the tracks from said notches by a relative rotative movement of the cover and the container, and a gasket carried by the flange, said tracks being constructed and arranged to wedge the top edge of the container against the' gasket and also to prevent the gasket from dropping out of the cover when the container is detachedtherefrom.

In testimony whereof, I have signed my name to this specification.

JAMES JARVIS PREBLE. 

